This type of targeting is only available to be applied at the level of the Ad.

For this reason, the feature is located on the “Add ads” page:

You can specify a minimum and maximum Width, and a minimum and maximum Height.

It is not obligatory to use all the options. That is why it is possible to set up only 1 value.

In order for this targeting to work, you should consider the following 3 points:

1- Type of Code to be used:
Ajax V4 (Multiple or per Space)

2- Size:
The system detects the browser’s visible area, not the entire navigator. Therefore, you should not write 800x600 or 1024x768, because the visible area would be smaller, for instance: 1016x544. This will depend on each monitor. If users have widescreen monitors, you should analyze which would be the browser’s visible area.

For example, there are 3 loaded ads with a targeting of:
a- maximum of 800x600
b- minimum of 800x600 up to a maximum of 1024x768
c- + than 1024x768

If the visible area is 1016x544, the banner to be shown would be the one which has the middle targeting, but not the others.

3- Priority:
You should upload 1 banner with priority 10 (lower than the rest of the ads of the campaign) in case all other priorities are not fulfilled due to widescreen monitors.